Intelligent outdoor lighting control system

ABSTRACT

A new and improved outdoor lighting control system for an outdoor lighting system network for automatically sensing, conveying, and recording data relevant to the operation of the lighting system network so that both control and maintenance can be performed more efficiently. At each of plural lamp locations in the network, there is a controller module that receives electric power input and that supplies electric power to the remaining lamp locations. Each controller module has a first relay to deliver current to one or more outdoor illumination lamps at the controller module&#39;s location, and a second relay for switching electric power on to a succeeding lamp location. A first current sensor monitors current to the lamps at each lamp location, and a second current sensor monitors current to the remaining locations. The network&#39;s power lines form portions of a bi-directional data link via which data is transmitted from each controller module to a command station, and vice versa.

This application is a Continuation of U.S. Ser. No. 09/412,695, filedOct. 5, 1999, now U.S. Pat. No. 6,204,615, which is a divisional of U.S.Ser. No. 08/804,714, filed Feb. 21, 1997 now issued U.S. Pat. No.5,962,991.

FIELD OF THE INVENTION

This invention relates generally to outdoor lighting control systems,and is especially advantageous for street and road lighting systems.

BACKGROUND AND SUMMARY OF THE INVENTION

Certain individuals and governments consider both ownership and use ofmotor vehicles as a social concession which is compensated and checkedby the levying of duties and various taxes on the vehicles and onproducts used in conjunction with the motor vehicles, especially fuels.Ownership of motor vehicles is however increasing throughout the world,and this is at least to significant extent attributable to increasedprosperity. As a result, there is increased demand for newinfrastructure, such as new streets, roads, highways, expressways,parking lots, etc., to accommodate both the increasing number of motorvehicles and the presence of more luxurious vehicles. Existinginfrastructure is often outdated and needs maintenance, upgrading,and/or replacement.

One important component of both existing and new infra-structure islighting systems for streets, roads, highways, expressways, parkinglots, etc. While lighting systems are primarily intended to befunctional, in some traditional areas, such as airports and shoppingmalls, it is important that they have a decorative character. Decorativecharacter of lighting systems is becoming more important especiallywhere the lighting systems are in the presence of illuminated signageand lighted buildings. Increased cost per unit of land area will beaccompanied by an increase in the amount of lighting cost per unit ofland area. Infra-structure associated with streets, roads, highways,expressways, parking lots, etc. requires maintenance. Because ofextensive daylight usage of these corridors of travel, maintenance isoften performed at night. If daylight maintenance is performed, it ofteninterferes with use of streets, roads, highways, expressways, parkinglots, etc. Because of increased traffic volumes, higher speeds, etc.,one can appreciate that performance of maintenance involves increasedrisks of accidental, and even fatal, harm to maintenance workers and tooccupants of motor vehicles.

Therefore, there is an increasing need for lighting installations thatare easier and more cost-effective to maintain. This is why sox catenaryinstallations are becoming less popular while the less efficientconventional SON-T installations with 18 meter high light poles placedup to 80 meters apart are increasingly popular.

One general objective of the present invention is to provide a new andimproved system for automatically sensing, conveying, and recording datarelevant to the operation of a lighting system network so thatmaintenance can be performed more efficiently.

Another general objective of the present invention is to provide a newand improved system for automatically controlling the operation of alighting system network more efficiently.

The present invention utilizes known electrical components organized andarranged in a lighting system in a way that has never been done before.

One general aspect of the invention relates to an outdoor lightingcontrol system for a string of outdoor illumination lamps disposed atvarious locations along an outdoor lighting system comprising: for eachof plural lamp locations in the string, a controller module comprisinginput means for receiving electric power input and output means forsupplying electric power to the remainder of the string; each of saidplural lamp locations further comprising one or more outdoorillumination lamps; each controller module comprising first switchingmeans for switching the electric power input to deliver current to theone or more outdoor illumination lamps at the controller module'slocation, and second switching means for switching electric input powerfrom the controller module's input means to the controller module'soutput means in response to receipt of electric power input at thecontroller module's input means.

The foregoing, and other features, along with various advantages andbenefits of the invention, will be seen in the ensuing description whichis accompanied by drawings. The drawings disclose a preferred embodimentof the invention according to the best mode contemplated at this timefor carrying out the invention.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a view of a typical outdoor lighting system embodyingprinciples of the invention.

FIG. 2 is a block diagram of an installation at a lamp pole.

FIG. 3 is a more detailed block diagram of FIG. 2.

FIGS. 4 and 5 are still more detailed diagrams.

FIG. 6 is a diagram of a central control room.

FIG. 7 is a chart showing functions performed by a controller module ina lamp pole and functions performed by a control computer.

FIG. 8 is a block diagram of a control for executing functions.

DESCRIPTION OF THE PREFERRED EMBODIMENT

FIG. 1 shows the general plan of a lighting system installationembodying principles of the present invention. There are a series oflight poles 10 (only one pole being shown in FIG. 1), each of which hasone or more lamps 12 for illuminating a land surface area. These polesare arranged in a string at appropriate distances, and in a givennetwork there can be any number of strings and any number of poles in astring. Power (240/480 volts typically) is delivered to the poles viapower lines 14, usually buried underground cables, and extending in astring from a lighting cabinet 16 that serves one or more strings in anetwork.

A network may have various numbers of such lighting cabinets 16 that arelinked with a central control room 18. Detail of an example of a centralcontrol room is shown in FIG. 6. Control room 18 receives electric powervia incoming power lines 20 and delivers that power to the variouslighting cabinets 16 via outgoing power lines 22. In addition, the powerlines 14, 22 provide a means for bi-direction communication and controlbetween the control room 18 on the one hand and the lighting cabinets 16and controller modules 27 in each pole 10 on the other hand. Data fromthe lighting cabinets and controller modules is conveyed to the controlroom, and commands are conveyed from the control room to the lightingcabinets and controller modules.

The control room is adapted for automatic operation to turn various lampstrings and/or individual lamps on and off at various times and tocollect data from the lighting cabinets and the lamps served from eachcabinet. The illustrated control room has a communication link 24 to theoutgoing power lines 22 which includes an IR module and adapter forlinking a P.C. 26 with the outgoing power lines while providingelectrical isolation between them.

FIGS. 1 and 2 shows each pole 10 to comprise a controller module 27 thathouses a lamp relay 28 via which electric power is delivered from powerlines 14 to the pole's lamp or lamps. According to certain principles ofthe invention, a switched power relay 30 and a LON chip 32 are alsoprovided within each controller module 27.

FIG. 3 shows further detail wherein each module 27 further comprisesvarious switches 34 that are operated by service personnel at time ofcomponent replacement for inputting to the LON chip 32 signals toindicate replacement of various components, such as the lamp, or lamps,12, the ballast, and the capacitor. Controller module 27 furthercomprises a power supply 36 that converts a small part of the incomingpower to suitable voltage for operating other module components,particularly the LON chip 32. There is also a LON power line interface38 that interfaces the LON chip with power lines 14. The lamp relay 28and the switched power relay 30 are connected with the LON chip 32.Current flow to the pole's lamp(s) is monitored by a current sensor 40which supplies a current measurement signal to an analog-to-digitalconverter 42. Lamp voltage is also supplied to the converter. Currentleaving the controller module via the switched power relay 30 ismonitored by a current sensor 44 that supplies a current measurementsignal to converter 42, and the voltage from switched power relay 30 issupplied as a voltage signal to the converter.

As will be explained in more detail below, the controller module 27 mayfit into a junction box at the base of the lights. The controller module27 may communicate with the PC 26 at least once a minute, but allowancesmay be made for an alarm mode.

The LON chip 32 is a device that provides certain functions at eachpole. It turns the pole's lamp(s) on and off by operating the lamp relay28 in accordance with commands received by module 27 via the incomingpower lines 14. It turns power to the next pole in the string on and offby operating the switched power relay 30 in accordance with commandsreceived by module 27 via the incoming power lines 14.

The LON chip 32 also provides data back to the control room 18 via thepower lines 22 and lighting cabinets 16. This data includes lampcurrent, lamp voltage, and signals for indicating that a new ballast, anew capacitor, or new lamps have been installed. Communication betweenthe LON chip 32 and power lines 14 is via interface 38.

At the central control station the usage of each lamp is logged so thata running count of hours on is maintained. Voltages and currents arealso logged. Any unusual event that causes an alarm to be given is alsologged. FIG. 7A is a chart describing various functions performed by acontroller module 27 in a lamp pole 10. The PC 26 runs computersoftware, which may have the functions listed in FIG. 7B. Although theFIG. 6 shows the PC at the control station, the PC may be locatedelsewhere and connected via suitable means, including for exampletelemetry and/or modems, with the interface to the power lines 22. At alighting cabinet 16, there may be conventional electrical equipment suchas a transformer or transformers that couples the incoming power lines22 to power lines 14 that serve the various strings of poles, variousdisconnects, etc. However, in certain installations, generally smallerinstallations, the equipment shown in control room 18 and the contentsof a lighting cabinet may be contained at a single site.

The data collection and control capabilities of the inventive controlsystem provide many possibilities for implementation in anyinstallation. Once important purpose is to monitor for abnormalconditions, such as lamp, ballast, and capacitor failure (either actualor impending) at each individual pole. Another purpose is to schedulepreventive maintenance. Another purpose is to monitor for line faults.The invention provides for communication between the control center andeach individual pole. Each individual pole is uniquely identified and sothe control center can communicate with the module 27 of each individualpole to ascertain its operating status and to collect information fromthe pole. If there is a failure or irregularity in a pole, the failureor irregularity is detected at the pole by the various sensing inputs tothe LON chip 32, either directly from a sensor, such as a currentsensor, or via interface 38. These are in turn communicated back via thepower lines (and through any intervening lighting cabinet) to thecontrol room. Personnel may or may not be in attendance at the controlroom. In event of emergency where no one is present, an alarm signal maybe transmitted to a person's personal beeper to alert the person.

The communication of data and commands via the power lines themselvesavoids the need for additional separate lines. The data and commands aretransmitted digitally on the power lines at voltages and frequenciesthat can be correctly transmitted and received without- interferencebetween these signals and the power line voltage and current.

It is to be noted that power cannot be transmitted from one pole to asubsequent pole in a string unless switched power relay 30 in the onepole is actuated closed by the LON chip 32 in the one pole. The LON chipis programmed to prevent relay 30 actuation unless conditions at the onepole are within specification for proper operation. If there is a faultbetween the one pole and a subsequent pole, it can be detected becausethe relay 30 of the one pole will be actuated closed, but there will beno communication with the subsequent pole. This capability quicklyprovides the location of a fault so that service personnel can godirectly to the location.

FIGS. 5 and 6 shows progressively greater detail of the circuitry ofmodule 27. FIG. 6 shows the lamp, the capacitor, and the ballastconnected in circuit with module 27. FIG. 5 shows the four individualswitches connected to the LON chip 32 each of which is actuated when thecorresponding component (lamp, ballast, capacitor) is replaced by a newone. This information is communicated to the control room to beginlogging new data for the new part or parts.

The LON chip 32 and interface 38 are conventional commercially availablecomponents. The LON chip and the PC are programmed by conventionalprogramming procedures to perform the various functions that have beendisclosed herein. A suitable LON chip is an Echelon Neuron Chip. Theinterface is also available from Echelon.

The flow chart shown in FIG. 8 comprises the following steps for thecontroller. First, a power on step command 100 applies power to thefirst controller module 27. The delivery of power to that module servesto initialize it via its LON chip 32, as represented by step 102. Step102 shows that the LON chip is placed in an initialized state thatcauses no power to be delivered to the lamp(s) of its pole or to thenext module 27 in the string of modules. The LON chip then returns a“controller stable” signal to P.C. 26, represented by step 104, toindicate that the first controller module is ready to receive a “lampon” command from the P.C.

Step 106 designates the “lamp on” command being given by the P.C. andreceived by the first controller module 27. That module responds to thatcommand by its LON chip 32 commanding its lamp relay 28 to turn on thelamp(s) of its pole, as represented by step 108. When the lamp(s) areturned on, the lamp circuit will, if it is operating properly, execute ashort electrical transient until the current and voltage stabilize. Whensteady state operation is detected, an appropriate signal or signals arereturned from the LON chip 32 to the P.C. so that operating times forthe lamp(s), ballast, and capacitor begin to be logged. Steady stateoperation can be detected by monitoring relevant current and/or voltage,or by waiting a sufficient amount of time for them to have stabilized ifthe circuit is operating properly. Step 108 shows that the current tothe lamp(s) is measured after the transient period, and a signalrepresenting that current is returned to the P.C. At the P.C. thatsignal is compared against proper current for that pole, and if themeasured current is within the proper range, the operating times for thelamp(s), ballast, and capacitor begin to be logged. If the signalindicates an out-of-range current, a possible fault condition is loggedfor investigation and possible corrective action. These series of stepsassociated with the turning on the lamp(s) of the first pole occurquickly, and they further include a step of the LON chip 32 operatingthe switched power relay 30 to enable voltage to be transmitted to thenext pole in the string, and communication to be established with theP.C.

The delivery of voltage to that next (second) pole in the string isfollowed by a “turn on next lamp” signal from the P.C. This isrepresented by the step 110 in FIG. 8. Upon receipt of that signal, thesecond pole's controller module 27 executes the same series of steps asdescribed above for the first pole, although FIG. 8 does not containblocks specifically repeating these steps. It is however to beunderstood that when the second pole's controller module receives its“turn on signal”, it responds to that command by its LON chip 32commanding its lamp relay 28 to turn on the lamp(s) of its pole. If itis operating properly, the lamp circuit will execute a short electricaltransient until the current and voltage stabilize. When steady stateoperation is detected, an appropriate signal or signals are returnedfrom the LON chip 32 to the P.C. so that operating times for the secondpole's lamp(s), ballast, and capacitor begin to be logged. Steady stateoperation is detected as described above for the first pole, current tothe lamp(s) is measured after the transient period, and a signalrepresenting that current is returned to the P.C. At the P.C. thatsignal is compared against proper current for that pole, and if themeasured current is within the proper range, the operating times for itslamp(s), ballast, and capacitor begin to be logged. If the signalindicates an out-of-range current, a possible fault condition is loggedfor investigation and possible corrective action. The turning on of thesecond pole's lamps is also accompanied by a step of its LON chip 32operating its switched power relay 30 to enable voltage to betransmitted to the next (third) pole in the string, and communication ofthe third pole's controller module 27 to be established with the P.C.

Based on the foregoing description, it can be understood that thisprocedure continues along the entire string until the lamps of the lastpole have been turned on. Any lamp circuit that is not operatingproperly will be logged. Operating times for each pole's components willbe logged. Thus information and history regarding the operation of eachpole is contained in the P;C., which may at times pass the informationto a central station. Problems with the string of poles can be detected,and a particular pole having a problem can be identified.

Steps 112 and 114 show how a problem can be identified. If a potentialproblem is signaled from any pole, or at any time that it is desired tocheck one or more of the poles, a “diagnostics” command is issued fromthe P.C. to a controller module 27. Upon receipt of that command thecommanded controller module 27 sends lamp current, voltage, log times,and next lamp current data back to the P.C. This is a reason why theexemplary current sensors 40 and 44 in each controller module 27 areimportant. Not only can the current flow into the lamps at each pole besent to the P.C., but the current flow from a controller module 27 tothe rest of the poles in the string can be ascertained. The P.C. isprogrammed with, or to calculate, what should be the proper currents andvoltages at various points in each pole, including the lamp(s), ballast,capacitor, and controller module. Upon receiving data from the poles,each of which is uniquely identified, the P.C. can compare that datawith the proper currents and voltages and thereby determine the locationand nature of a fault or faults. This will greatly aid service personnelwho must go out into the field to correct a problem.

The steps 116 and 118 depict a still further function that occurs ineach controller module after it has been turned on. As the LON chip 32operates the switched power relay 30 to deliver voltage to the nextpole, it also enables an overcurrent interrupt. If the current flow tothe next pole as sensed by sensor 44 is an overcurrent, the LON chipwill immediately stop the operation of relay 30 so that power flow fromits pole to the rest of the string is promptly terminated. A fault(alarm) signal is sent back to the P.C. to log the fault.

The remaining steps 120, 122 shown in FIG. 8 simply representintentionally turning off the string of lamps. The P.C. issues a “lampoff” command, and when it is received the poles are shut down. This canbe done in reverse order to “lamps on” so that each preceding pole in astring can supply final data to the P.C., if desired. Log off times arenoted by the P.C. so that component “on” time ceases to accumulate.

The invention therefore adds important capabilities in monitoring andservicing a string of outdoor lamps. While a presently preferredembodiment has been illustrated and described, it is to be appreciatedthat principles are applicable to other embodiments that fall within thescope of the following claims.

What is claimed is:
 1. An outdoor lighting control system for a stringof outdoor illumination lamps disposed at various locations along anoutdoor lighting system comprising: for each of plural lamp locations inthe string, a controller module comprising input means for receivingelectric power input and output means for supplying electric power tothe remainder of the string; each of said plural lamp locations furthercomprising one or more outdoor illumination lamps; each controllermodule comprising first switching means for switching the electric powerinput to deliver current to the one or more outdoor illumination lampsat the controller module's location, and second switching means forswitching electric input power from the controller module's input meansto the controller module's output means in response to receipt ofelectric power input at the controller module's input means.
 2. Anoutdoor lighting control system as set forth in claim 1 in which eachcontroller module comprises its own electronic control unit forcontrolling its first switching means and its second switching means. 3.An outdoor lighting control system as set forth in claim 2 in which eachof said first switching means is a first relay and each of said secondswitching means is a second relay.
 4. An outdoor lighting control systemas set forth in claim 2 in which each electronic control unit comprisesa LON chip.
 5. An outdoor lighting control system as set forth in claim1 in which each of said plural lamp locations further comprises a polecontaining said one or more outdoor illumination lamps, and eachcontroller module is disposed in the base of its pole.